What’s off-putting is those mega-dropdown menus; more complex than some entire web pages! Also what’s odd is the slight delay when you hover. I understand why some sites use it for rolloff, in case a user accidentally moves their cursor a few pixels outside and the menu doesn’t disappear immediately, but doing it for rollover seems strange.
For dropdown menus inside main navigation in general, I don’t know, I’ve never experienced any blowback to nix them or reconsider their use. I know there’s the issue of touch on mobile devices which makes hover behavior unexpected or outright nonexistent, but I think most people understand what purpose they serve and can deal with obstructed content. Good test case, but I haven’t encountered too many users who’ve been bothered by them obstructing content.